Allsky Camera

Intro

Nestled in the picturesque Huon Valley of Southern Tasmania, I’m privileged to witness breathtaking night skies, untainted by excessive light pollution. Moreover, my location at 42 degrees South affords me semi-regular glimpses of spectacular auroral displays. Seizing the opportunity to capture these celestial wonders, I embarked on building an Allsky camera in November 2023. If the camera is operational, it is available at https://allsky.rigby.systems/allsky/

The Allsky Project is an open-source initiative founded by Thomas Jacquin, with a dedicated team of developers contributing to its growth. I’d like to extend my gratitude to Eric Claeys, who provided valuable assistance when I integrated support for a new camera. This project empowers hobbyists to build astrophotography cameras capable of capturing the entire sky. The software features a configuration web server and public web server, automatically generating time-lapses, star trails, and keogram images at the end of each night. Running on a Raspberry Pi connected to a suitable camera, the software continuously captures images throughout the night, dynamically adjusting exposure and gain settings to produce exceptional photos of the night sky.

V1 - IMX462

I constructed my first all-sky camera utilizing a Sony IMX462 sensor from Arducam. This camera leverages Sony’s STARVIS sensor technology, boasting high-sensitivity, low-noise pixels. This results in brighter star captures at shorter exposure lengths, minimizing smearing caused by the Earth’s rotation. To house the camera, I employed an IP67 enclosure from Jaycar, an acrylic dome from Amazon, and gasket paper from Repco. The camera was installed at the Huon Bush Retreats, where I was fortunate enough to capture a stunning timelapse of the Aurora on May 12th, 2024 – viewable below.

V2 - IR Sensitive & Solar Powered

Version two of my all-sky camera incorporated several key upgrades. Firstly, I replaced the acrylic dome with interchangeable acrylic discs, which proved to be a cost-effective solution ($20 for 30 discs on eBay) to mitigate the effects of Tasmania’s harsh UV weathering. Additionally, I designed a custom heater PCB to warm the lens and prevent condensation accumulation. The most significant enhancement, however, was the integration of a solar power supply. I purchased a 100W solar panel and a LiFePO4 battery on eBay, enabling the camera to operate independently. To extend the camera’s connectivity, I added an external WiFi antenna using a UFL connector soldered to the Raspberry Pi. My plan was to design 3D-printed parabolic reflectors for the antenna, both at the camera location and my house, allowing me to position the camera further up the hill without interference from passing drivers’ headlights. As a nod to my interest in UFOs, I also removed the IR filter from the camera, enabling it to capture infrared light in addition to visible light. This modification takes advantage of the camera’s pixel sensitivity to infrared light, which is normally blocked by the filter.

According to UAP (Unidentified Aerial Phenomena) enthusiasts, some “orbs” are reportedly more visible – or even exclusively visible – in the infrared spectrum. By removing the IR filter, my all-sky camera may be able to capture some of these elusive phenomena. Indeed, without the filter, the camera detected more stars and objects moving relative to the stars. However, none of these objects exhibited unusual movement patterns that couldn’t be attributed to satellites. It’s worth noting that the IR filter, like all real-world filters, isn’t perfect and does reduce the intensity of visible light passing through. For stargazing, removing the filter is beneficial. However, there’s a trade-off: RGB pixels have a secondary sensitivity peak in the IR spectrum, which means that aurorae – emitting both visible and infrared light – can trigger all RGB pixels, resulting in a washed-out, white appearance in the captured imagery.

While the infrared view has its own merits, it can’t compare to the breathtaking spectacle of an aurora visible in the visible spectrum alone. For this reason, I’ve decided to revert to a camera with the “No IR” filter for Version 3.

V3 - 4G Modem and Space Probe Frame

I’m currently building Version 3 of my all-sky camera, which boasts several exciting new features:

• A robotic camera head with pan and tilt capabilities, allowing for manual exploration and programmable motion control during time-lapses.
• A solar panel array consisting of two 100W panels mounted on a sun-tracking frame, ensuring consistent power supply even on cloudy days.
• A GL.Inet 4G IoT modem, enabling remote connectivity and placement anywhere with cellular reception.
• A futuristic, probe-inspired design complete with a mock rocket nozzle, giving the camera the appearance of a landed space probe.